A Phase 3 interventional study of Placebo Matching Mitapivat and Mitapivat in Non-Transfusion-dependent Alpha-Thalassemia and Non-Transfusion-dependent Beta-Thalassemia, sponsored by Agios Pharmaceuticals, Inc.. Active, not recruiting at 68 sites in 18 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-28.
Sponsored by Agios Pharmaceuticals, Inc. · Phase 3, Interventional, and Treatment
The primary purpose of this study was to compare the effect of mitapivat versus placebo on hemolytic anemia in participants with alpha- or beta-non-transfusion dependent thalassemia (NTDT).
The mitapivat group included 130 participants whereas the placebo group had 64 participants.
Agios Pharmaceuticals, Inc. is the lead sponsor of 52 studies on the registry; 6 are open to participants now.
Of its 23 completed or terminated interventional studies of FDA-regulated products, 4 (17%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Any medical, hematological, psychological, or behavioral condition(s) or prior or current therapy that, in the opinion of the Investigator, may confer an unacceptable risk to participating in the study and/or could confound the interpretation of the study data Also excluded are:
Mitapivat 100 milligrams (mg), orally, twice daily (BID) for 24 weeks in double blind (DB) period and for up to 5 years in open label extension (OLE) period.
Drug: Mitapivat
Placebo matching mitapivat, orally, BID for 24 weeks in double blind period followed by Mitapivat 100 mg, orally, BID for up to 5 years in open label extension period.
Drug: Placebo Matching Mitapivat · Drug: Mitapivat
Tablets
Tablets
Also known as: AG-348, AG-348 sulfate hydrate, Mitapivat sulfate
Double-Blind Period: Percentage of Participants Who Achieved Hemoglobin (Hb) Response From Week 12 Through Week 24 Compared With Baseline
Hb response is defined as ≥10 grams/ liter (g/L) (1.0 gram per deciliter) (g/dL) increase in average Hb concentration from Week 12 through Week 24 compared with baseline. Hb response was tested using the Mantel-Haenszel stratum weighted method adjusting for randomization stratification factors. Baseline is defined as the average of all assessments within 42 days before randomization for subjects randomized and not dosed or within 42 days before the start of study treatment for subjects randomized and dosed.
Time frame: Double-Blind Period: Baseline up to Week 12 through Week 24
Double-Blind Period: Change From Baseline in Average Functional Assessment of Chronic Illness Therapy (FACIT) -Fatigue Subscale Score From Week 12 Through Week 24
The FACIT-Fatigue subscale includes a 13-item self-reported fatigue subscale, which assesses the severity and impact of fatigue (including the impact on daily activities and functioning).The FACIT-Fatigue subscale is scored on a 5-point Likert scale: 0 (not at all) to 4 (very much). The total FACIT-Fatigue subscale score ranges from 0 to 52, with a higher score indicating better health-related quality of life (HRQOL). Baseline is defined as the last assessment before randomization for subjects randomized and not dosed or the last assessment before start of study treatment for subjects randomized and dosed.
Time frame: Double-Blind Period: Baseline, Week 12 through Week 24
Double-Blind Period: Change From Baseline in Average Hb Concentration From Week 12 Through Week 24
Baseline is defined as the average of all assessments within 42 days before randomization for subjects randomized and not dosed or within 42 days before the start of study treatment for subjects randomized and dosed.
Time frame: Double-Blind Period: Baseline, Week 12 through Week 24
Double-Blind Period: Percentage of Participants Who Achieved Hb 1.5+ Response From Week 12 Through Week 24 Compared With Baseline
Hb 1.5+ response is defined as a ≥1.5 g/dL increase in average Hb concentration from Week 12 through Week 24 compared with baseline. Hb 1.5+ response will be summarized using the Mantel-Haenszel stratum weighted method adjusting for randomization stratification factors. Baseline is defined as the average of all assessments within 42 days before randomization for subjects randomized and not dosed or within 42 days before the start of study treatment for subjects randomized and dosed.
Time frame: Double-Blind Period: Baseline up to Week 12 through Week 24
Double-Blind Period: Change From Baseline in Indirect Bilirubin at Week 24
Baseline is defined as the average of all assessments within 42 days before randomization for subjects randomized and not dosed or within 42 days before the start of study treatment for subjects randomized and dosed.
Time frame: Double-Blind Period: Baseline, Week 24
Double-Blind Period: Change From Baseline in Lactate Dehydrogenase (LDH) at Week 24
Baseline is defined as the average of all assessments within 42 days before randomization for subjects randomized and not dosed or within 42 days before the start of study treatment for subjects randomized and dosed.
Time frame: Double-Blind Period: Baseline, Week 24
Double-Blind Period: Change From Baseline in Haptoglobin at Week 24
Baseline is defined as the average of all assessments within 42 days before randomization for subjects randomized and not dosed or within 42 days before the start of study treatment for subjects randomized and dosed.
Time frame: Double-Blind Period: Baseline, Week 24
Double-Blind Period: Change From Baseline in Reticulocytes at Week 24
Baseline is defined as the average of all assessments within 42 days before randomization for subjects randomized and not dosed or within 42 days before the start of study treatment for subjects randomized and dosed.
Time frame: Double-Blind Period: Baseline, Week 24
Double-Blind Period: Change From Baseline in Erythropoietin at Week 24
Baseline is defined as the average of all assessments within 42 days before randomization for subjects randomized and not dosed or within 42 days before the start of study treatment for subjects randomized and dosed.
Time frame: Double-Blind Period: Baseline, Week 24
Double-Blind Period: Percentage of Participants Who Achieved Patient Global Impression of Severity (PGIS)- Fatigue Response at Weeks 12, 16, 20, and 24
PGIS-Fatigue measured participants' perception of their fatigue severity (7-day recall) on a 4-point scale ranging from '1=none' to '4=severe'. A participant was considered to have achieved the PGIS-Fatigue response at Weeks 12, 16, 20, or 24, if their baseline to postbaseline score met one of the following conditions: 'none' at baseline to 'none' postbaseline; 'mild' to 'mild' or 'none'; 'moderate' to 'mild' or 'none'; or 'severe' to 'moderate', 'mild', or 'none'.
Time frame: Double-Blind Period: At Weeks 12, 16, 20, and 24
Double-Blind Period: Percentage of Participants Who Achieved the Patient Global Impression of Change (PGIC)- Fatigue Response at Weeks 12, 16, 20, and 24
The PGIC-Fatigue assesses change over time compared with baseline on a 5-point scale ranging from 0 to 4 where 0 indicates Much better and 4 as Much worse. A participant was considered to have achieved the PGIC-Fatigue response at Weeks 12, 16, 20, or 24 if their baseline PGIS and corresponding PGIC met one of the following conditions: if the PGIS at baseline was 'none' or 'mild' and PGIC at the visit was 'no change', 'a little better', or 'much better'; or if the PGIS at baseline was 'moderate' or 'severe' and PGIC at the visit was 'a little better' or 'much better'.
Time frame: Double-Blind Period: At Weeks 12, 16, 20, and 24
Double-Blind Period: Change From Baseline in the 6-minute Walk Test (6MWT) Distance at Week 24
The 6MWT is a well-established performance outcome (PerfO) measure that is widely used to evaluate physical activity in terms of distance walked in patients with a variety of conditions. The test measures the distance an individual can walk on a hard, flat surface in 6 minutes.
Time frame: Double-Blind Period: Baseline, Week 24
Double-Blind Period: Change From Baseline in Serum Ferritin at Week 24
Iron metabolism was assessed based on serum ferritin levels.
Time frame: Double-Blind Period: Baseline, Week 24
Double-Blind Period: Change From Baseline in Transferrin Saturation (TSAT) at Week 24
Iron metabolism was assessed based on TSAT levels. Transferrin saturation is reported by dividing value of serum iron by total iron binding capacity.
Time frame: Double-Blind Period: Baseline, Week 24
Double-Blind Period: Number of Participants With Treatment-Emergent Adverse Events (TEAEs), Serious TEAEs, Related TEAEs and TEAEs With Severity Greater Than or Equal to Grade 3
AE is any untoward medical occurrence in a participant administered a pharmaceutical product and which does not necessarily have a causal relationship with the study drug. A serious adverse event (SAE) is any untoward medical occurrence that resulted in any of the following outcomes: death; life threatening; persistent/significant disability/incapacity; initial or prolonged inpatient hospitalization; congenital anomaly/birth defect or was otherwise considered medically important. TEAEs are AEs with an initial onset date during the on-treatment period or worsening from baseline and includes both serious \& non-serious TEAEs. Severity of AEs was evaluated using the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE; Version 4.03): grade 1: mild; grade 2: moderate; grade 3: severe or medically significant but not immediately life-threatening; grade 4: life threatening or disabling; grade 5: death related to AE.
Time frame: Double-Blind Period: From the time of signing informed consent to Week 24
Double-Blind Period: Plasma Concentration of Mitapivat
Time frame: Double-Blind Period: Pre-dose at Week 12; pre-dose, 0.5, 1, 3, 5, 7 hours post-dose at Week 20
Double-Blind Period: Area Under the Plasma Concentration-time Curve From Time Zero to the Last Measurable Concentration (AUC0-last) of Mitapivat
Area under the concentration-time curve from time zero to Tlast on dosing day, calculated using the linear-log trapezoidal rule.
Time frame: Double-Blind Period: Pre-dose, 0.5, 1, 3, 5, 7 hours post-dose at Week 20
Double-Blind Period: Time of Last Quantifiable Concentration (Tlast) of Mitapivat
Time frame: Double-Blind Period: Pre-dose, 0.5, 1, 3, 5, 7 hours post-dose at Week 20
Double-Blind Period: Maximum Observed Plasma Concentration (Cmax) of Mitapivat
Time frame: Double-Blind Period: Pre-dose, 0.5, 1, 3, 5, 7 hours post-dose at Week 20
Double-Blind Period: Time to Reach Maximum Observed Plasma Concentration (Tmax) of Mitapivat
Time frame: Double-Blind Period: Pre-dose, 0.5, 1, 3, 5, 7 hours post-dose at Week 20
Double-Blind Period: Last Quantifiable Plasma Concentration (Clast) of Mitapivat
Time frame: Double-Blind Period: Pre-dose, 0.5, 1, 3, 5, 7 hours post-dose at Week 20
Double-Blind Period: Blood Concentration of Adenosine Triphosphate (ATP)
Time frame: Double-Blind Period: Pre-dose at Day 1; pre-dose at Week 12; pre-dose, 0.5, 1, 3, 5, 7 hours post-dose at Week 20
Double-Blind Period: Blood Concentration of 2,3 - Diphosphoglycerate (2,3-DPG)
Time frame: Double-Blind Period: Pre-dose at Day 1; pre-dose at Week 12; pre-dose, 0.5, 1, 3, 5, 7 hours post-dose at Week 20
Open-Label Extension Period: Number of Participants With Treatment-Emergent Adverse Events (TEAEs), Serious TEAEs, Related TEAEs and TEAEs With Severity of Greater Than or Equal to Grade 3
AE is any untoward medical occurrence in a participant administered a pharmaceutical product and which does not necessarily have a causal relationship with the study drug. A serious adverse event (SAE) is any untoward medical occurrence that resulted in any of the following outcomes: death; life threatening; persistent/significant disability/incapacity; initial or prolonged inpatient hospitalization; congenital anomaly/birth defect or was otherwise considered medically important. TEAEs are AEs with an initial onset date during the on-treatment period or worsening from baseline and includes both serious \& non-serious TEAEs. Severity of abnormalities was evaluated using the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE; Version 4.03): grade 1: mild; grade 2: moderate; grade 3: severe or medically significant but not immediately life-threatening; grade 4: life threatening or disabling; grade 5: death related to AE.
Time frame: Open-Label Extension Period: From week 24 up to end of study (approximately 5 years)
Participants took part in study at study sites in the United States of America, Brazil, Bulgaria, Canada, Denmark, France, Greece, Italy, Lebanon, Malaysia, Netherlands, Saudi Arabia, Spain, Taiwan, Thailand, Turkey, United Arab Emirates and the United Kingdom. Results are reported for 24-week DB period until primary completion date. Analysis of data for OLE period is still ongoing with anticipated completion in December 2028. Results for OLE period will be reported by December 2029.
| Milestone | Mitapivat | Placebo |
|---|---|---|
| Started | 130 | 64 |
| Treated | 129 | 63 |
| Completed | 122 | 62 |
| Not completed | 8 | 2 |
| Withdrew: Randomized, never treated | 1 | 1 |
| Withdrew: Withdrawal by subject | 3 | 1 |
| Withdrew: Adverse event | 2 | 0 |
| Withdrew: Pregnancy | 1 | 0 |
| Withdrew: Other un-specified | 1 | 0 |
Hb response is defined as ≥10 grams/ liter (g/L) (1.0 gram per deciliter) (g/dL) increase in average Hb concentration from Week 12 through Week 24 compared with baseline. Hb response was tested using the Mantel-Haenszel stratum weighted method adjusting for randomization stratification factors. Baseline is defined as the average of all assessments within 42 days before randomization for subjects randomized and not dosed or within 42 days before the start of study treatment for subjects randomized and dosed.
| Percentage of participants | Mitapivat | Placebo |
|---|---|---|
| Double-Blind Period: Percentage of Participants Who Achieved Hemoglobin (Hb) Response From Week 12 Through Week 24 Compared With Baseline | 42.3 | 1.6 |
The FACIT-Fatigue subscale includes a 13-item self-reported fatigue subscale, which assesses the severity and impact of fatigue (including the impact on daily activities and functioning).The FACIT-Fatigue subscale is scored on a 5-point Likert scale: 0 (not at all) to 4 (very much). The total FACIT-Fatigue subscale score ranges from 0 to 52, with a higher score indicating better health-related quality of life (HRQOL). Baseline is defined as the last assessment before randomization for subjects randomized and not dosed or the last assessment before start of study treatment for subjects randomized and dosed.
| score on a scale | Mitapivat | Placebo |
|---|---|---|
| Double-Blind Period: Change From Baseline in Average Functional Assessment of Chronic Illness Therapy (FACIT) -Fatigue Subscale Score From Week 12 Through Week 24 | 4.85 ± 0.732 | 1.46 ± 0.955 |
Baseline is defined as the average of all assessments within 42 days before randomization for subjects randomized and not dosed or within 42 days before the start of study treatment for subjects randomized and dosed.
| Gram per Liter (g/L) | Mitapivat | Placebo |
|---|---|---|
| Double-Blind Period: Change From Baseline in Average Hb Concentration From Week 12 Through Week 24 | 8.57 ± 0.666 | -1.06 ± 0.867 |
Hb 1.5+ response is defined as a ≥1.5 g/dL increase in average Hb concentration from Week 12 through Week 24 compared with baseline. Hb 1.5+ response will be summarized using the Mantel-Haenszel stratum weighted method adjusting for randomization stratification factors. Baseline is defined as the average of all assessments within 42 days before randomization for subjects randomized and not dosed or within 42 days before the start of study treatment for subjects randomized and dosed.
| Percentage of participants | Mitapivat | Placebo |
|---|---|---|
| Double-Blind Period: Percentage of Participants Who Achieved Hb 1.5+ Response From Week 12 Through Week 24 Compared With Baseline | 24.6 | 0 |
Baseline is defined as the average of all assessments within 42 days before randomization for subjects randomized and not dosed or within 42 days before the start of study treatment for subjects randomized and dosed.
| Micromole per Liter (umol/L) | Mitapivat | Placebo |
|---|---|---|
| Double-Blind Period: Change From Baseline in Indirect Bilirubin at Week 24 | -10.65 ± 1.047 | -0.03 ± 1.403 |
Baseline is defined as the average of all assessments within 42 days before randomization for subjects randomized and not dosed or within 42 days before the start of study treatment for subjects randomized and dosed.
| Units per Liter (U/L) | Mitapivat | Placebo |
|---|---|---|
| Double-Blind Period: Change From Baseline in Lactate Dehydrogenase (LDH) at Week 24 | -30.07 ± 7.131 | -5.79 ± 9.440 |
Baseline is defined as the average of all assessments within 42 days before randomization for subjects randomized and not dosed or within 42 days before the start of study treatment for subjects randomized and dosed.
| Gram per Liter (g/L) | Mitapivat | Placebo |
|---|---|---|
| Double-Blind Period: Change From Baseline in Haptoglobin at Week 24 | -0.002 ± 0.0145 | 0.017 ± 0.0199 |
Baseline is defined as the average of all assessments within 42 days before randomization for subjects randomized and not dosed or within 42 days before the start of study treatment for subjects randomized and dosed.
| 10^9 cells per liter (10^9 cells/L) | Mitapivat | Placebo |
|---|---|---|
| Double-Blind Period: Change From Baseline in Reticulocytes at Week 24 | -32.11 ± 10.600 | -14.74 ± 14.932 |
Baseline is defined as the average of all assessments within 42 days before randomization for subjects randomized and not dosed or within 42 days before the start of study treatment for subjects randomized and dosed.
| International units per Liter (IU/L) | Mitapivat | Placebo |
|---|---|---|
| Double-Blind Period: Change From Baseline in Erythropoietin at Week 24 | 19.21 ± 37.773 | 115.71 ± 49.413 |
PGIS-Fatigue measured participants' perception of their fatigue severity (7-day recall) on a 4-point scale ranging from '1=none' to '4=severe'. A participant was considered to have achieved the PGIS-Fatigue response at Weeks 12, 16, 20, or 24, if their baseline to postbaseline score met one of the following conditions: 'none' at baseline to 'none' postbaseline; 'mild' to 'mild' or 'none'; 'moderate' to 'mild' or 'none'; or 'severe' to 'moderate', 'mild', or 'none'.
| percentage of participants | Mitapivat | Placebo |
|---|---|---|
| At Week 12 | 65.4 | 46.9 |
| At Week 16 | 63.1 | 42.2 |
| At Week 20 | 61.5 | 48.4 |
| At Week 24 | 62.3 | 46.9 |
The PGIC-Fatigue assesses change over time compared with baseline on a 5-point scale ranging from 0 to 4 where 0 indicates Much better and 4 as Much worse. A participant was considered to have achieved the PGIC-Fatigue response at Weeks 12, 16, 20, or 24 if their baseline PGIS and corresponding PGIC met one of the following conditions: if the PGIS at baseline was 'none' or 'mild' and PGIC at the visit was 'no change', 'a little better', or 'much better'; or if the PGIS at baseline was 'moderate' or 'severe' and PGIC at the visit was 'a little better' or 'much better'.
| percentage of participants | Mitapivat | Placebo |
|---|---|---|
| At Week 12 | 71.5 | 53.1 |
| At Week 16 | 71.5 | 50.0 |
| At Week 20 | 66.2 | 56.3 |
| At Week 24 | 66.2 | 53.1 |
The 6MWT is a well-established performance outcome (PerfO) measure that is widely used to evaluate physical activity in terms of distance walked in patients with a variety of conditions. The test measures the distance an individual can walk on a hard, flat surface in 6 minutes.
| Meters | Mitapivat | Placebo |
|---|---|---|
| Double-Blind Period: Change From Baseline in the 6-minute Walk Test (6MWT) Distance at Week 24 | 30.48 ± 5.651 | 7.11 ± 7.346 |
Iron metabolism was assessed based on serum ferritin levels.
| Microgram/Liter (mcg/L) | Mitapivat | Placebo |
|---|---|---|
| Double-Blind Period: Change From Baseline in Serum Ferritin at Week 24 | -34.75 ± 32.710 | -32.48 ± 43.090 |
Iron metabolism was assessed based on TSAT levels. Transferrin saturation is reported by dividing value of serum iron by total iron binding capacity.
| Ratio | Mitapivat | Placebo |
|---|---|---|
| Double-Blind Period: Change From Baseline in Transferrin Saturation (TSAT) at Week 24 | -0.029 ± 0.0212 | -0.047 ± 0.0262 |
AE is any untoward medical occurrence in a participant administered a pharmaceutical product and which does not necessarily have a causal relationship with the study drug. A serious adverse event (SAE) is any untoward medical occurrence that resulted in any of the following outcomes: death; life threatening; persistent/significant disability/incapacity; initial or prolonged inpatient hospitalization; congenital anomaly/birth defect or was otherwise considered medically important. TEAEs are AEs with an initial onset date during the on-treatment period or worsening from baseline and includes both serious \& non-serious TEAEs. Severity of AEs was evaluated using the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE; Version 4.03): grade 1: mild; grade 2: moderate; grade 3: severe or medically significant but not immediately life-threatening; grade 4: life threatening or disabling; grade 5: death related to AE.
| Participants | Mitapivat | Placebo |
|---|---|---|
| Participants with TEAEs | 107 | 50 |
| Participants with Serious TEAEs | 8 | 0 |
| Participants with TEAEs related to study drug | 56 | 13 |
| Participants with any TEAE of Grade ≥ 3 | 18 | 2 |
| nanograms per milliliter (ng/mL) | Mitapivat |
|---|---|
| Pre-dose at Week 12 | 59.23 ± 51.081 |
| Pre-dose at Week 20 | 84.70 ± 138.852 |
| 30 Minutes Post-dose at Week 20 | 1209.00 ± 931.211 |
| 1 Hour Post-dose at Week 20 | 1386.35 ± 712.996 |
| 3 Hour Post-dose at Week 20 | 740.26 ± 357.660 |
| 5 Hour Post-dose at Week 20 | 359.42 ± 269.758 |
| 7 Hour Post-dose at Week 20 | 206.82 ± 185.657 |
Area under the concentration-time curve from time zero to Tlast on dosing day, calculated using the linear-log trapezoidal rule.
| Hours*nanogram per milliliter (h*ng/mL) | Mitapivat |
|---|---|
| Double-Blind Period: Area Under the Plasma Concentration-time Curve From Time Zero to the Last Measurable Concentration (AUC0-last) of Mitapivat | 4262.57 ± 31.4 |
| hours | Mitapivat |
|---|---|
| Double-Blind Period: Time of Last Quantifiable Concentration (Tlast) of Mitapivat | 6.825 (6.50 to 7.42) |
| ng/mL | Mitapivat |
|---|---|
| Double-Blind Period: Maximum Observed Plasma Concentration (Cmax) of Mitapivat | 1565.69 ± 42.4 |
| Hours | Mitapivat |
|---|---|
| Double-Blind Period: Time to Reach Maximum Observed Plasma Concentration (Tmax) of Mitapivat | 1.000 (0.20 to 5.00) |
| ng/mL | Mitapivat |
|---|---|
| Double-Blind Period: Last Quantifiable Plasma Concentration (Clast) of Mitapivat | 166.93 ± 80.1 |
| microgram/milliliter (mcg/mL) | Mitapivat | Placebo |
|---|---|---|
| At Pre-dose at Day 1 | 180.87 ± 29.577 | 184.91 ± 31.299 |
| Pre-dose at Week 12 | 242.07 ± 45.782 | 176.81 ± 33.657 |
| Pre-dose at Week 20 | 235.79 ± 46.099 | 168.10 ± 29.962 |
| 30 Minutes Post-dose at Week 20 | 417.87 ± 102.853 | 457.78 ± 89.932 |
| 1 Hour Post-dose at Week 20 | 417.83 ± 105.752 | 457.71 ± 104.431 |
| 3 Hour Post-dose at Week 20 | 409.73 ± 96.379 | 454.39 ± 107.966 |
| 5 Hour Post-dose at Week 20 | 412.72 ± 94.150 | 464.24 ± 97.007 |
| 7 Hour Post-dose at Week 20 | 404.43 ± 97.586 | 471.10 ± 113.165 |
| mcg/mL | Mitapivat | Placebo |
|---|---|---|
| Pre-dose at Day 1 | 526.40 ± 125.196 | 506.14 ± 108.033 |
| Pre-dose at Week 12 | 434.90 ± 97.901 | 497.68 ± 112.055 |
| Pre-dose at Week 20 | 426.30 ± 107.173 | 468.22 ± 99.783 |
| 30 Minutes Post-dose at Week 20 | 417.87 ± 102.853 | 457.78 ± 89.932 |
| 1 Hour Post-dose at Week 20 | 417.83 ± 105.752 | 457.71 ± 104.431 |
| 3 Hour Post-dose at Week 20 | 409.73 ± 96.379 | 454.39 ± 107.966 |
| 5 Hour Post-dose at Week 20 | 412.72 ± 94.150 | 464.24 ± 97.007 |
| 7 Hour Post-dose at Week 20 | 404.43 ± 97.586 | 471.10 ± 113.165 |
AE is any untoward medical occurrence in a participant administered a pharmaceutical product and which does not necessarily have a causal relationship with the study drug. A serious adverse event (SAE) is any untoward medical occurrence that resulted in any of the following outcomes: death; life threatening; persistent/significant disability/incapacity; initial or prolonged inpatient hospitalization; congenital anomaly/birth defect or was otherwise considered medically important. TEAEs are AEs with an initial onset date during the on-treatment period or worsening from baseline and includes both serious \& non-serious TEAEs. Severity of abnormalities was evaluated using the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE; Version 4.03): grade 1: mild; grade 2: moderate; grade 3: severe or medically significant but not immediately life-threatening; grade 4: life threatening or disabling; grade 5: death related to AE.
Results for this outcome have not been posted.
Collected over Double-blind period: From the time of signing informed consent to Week 24. Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Mitapivat | 0/130 (0%) | 8/129 (6.2%) | 80/129 (62%) |
| Placebo | 0/64 (0%) | 0/63 (0%) | 33/63 (52.4%) |
| Event | Mitapivat | Placebo |
|---|---|---|
| Lower respiratory tract infectionInfections and infestations | 1/129 | 0/63 |
| PneumoniaInfections and infestations | 1/129 | 0/63 |
| Upper respiratory tract infectionInfections and infestations | 1/129 | 0/63 |
| Craniofacial fractureInjury, poisoning and procedural complications | 1/129 | 0/63 |
| Ulna fractureInjury, poisoning and procedural complications | 1/129 | 0/63 |
| AnaemiaBlood and lymphatic system disorders | 1/129 | 0/63 |
| Angina pectorisCardiac disorders | 1/129 | 0/63 |
| Abdominal painGastrointestinal disorders | 1/129 | 0/63 |
| Superficial vein thrombosisVascular disorders | 1/129 | 0/63 |
| Event | Mitapivat | Placebo |
|---|---|---|
| HeadacheNervous system disorders | 29/129 | 6/63 |
| Initial insomniaPsychiatric disorders | 18/129 | 3/63 |
| NauseaGastrointestinal disorders | 15/129 | 5/63 |
| Upper respiratory tract infectionInfections and infestations | 13/129 | 4/63 |
| InfluenzaInfections and infestations | 5/129 | 6/63 |
| DiarrhoeaGastrointestinal disorders | 11/129 | 6/63 |
| PyrexiaGeneral disorders | 4/129 | 6/63 |
| FatigueGeneral disorders | 12/129 | 4/63 |
| COVID-19Infections and infestations | 8/129 | 5/63 |
| Back painMusculoskeletal and connective tissue disorders | 3/129 | 5/63 |
Full Analysis Set (FAS) included all participants who were randomized.
| Age, Continuous(years) | Mitapivat | Placebo | Total |
|---|---|---|---|
| Mean | 42.4 ± 13.03 | 38.9 ± 12.99 | 41.2 ± 13.09 |
| Sex: Female, Male(Participants) | Mitapivat | Placebo | Total |
|---|---|---|---|
| Female | 84 | 39 | 123 |
| Male | 46 | 25 | 71 |
| Ethnicity (NIH/OMB)(Participants) | Mitapivat | Placebo | Total |
|---|---|---|---|
| Hispanic or Latino | 11 | 6 | 17 |
| Not Hispanic or Latino | 118 | 58 | 176 |
| Unknown or Not Reported | 1 | 0 | 1 |
| Race/Ethnicity, Customized(Participants) | Mitapivat | Placebo | Total |
|---|---|---|---|
| White | 73 | 36 | 109 |
| Asian | 52 | 24 | 76 |
| Black or African American | 1 | 1 | 2 |
| American Indian or Alaska Native | 0 | 0 | 0 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 |
| Multiracial | 1 | 0 | 1 |
| Unknown | 2 | 2 | 4 |
| Not reported | 1 | 1 | 2 |
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Agios Pharmaceuticals, Inc.